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pokey: yet another performance enhancement (#4735)

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* pokey: yet another performance enhancement

In case

* no counters are running at high speed without prescalers - and
* no prescalers have triggered - and
* there is no borrow counter expected to finish

there is no need to continue on step_one_clock.

Performance measuements:
Before:
./mame64 -bench 50 missile -> Average speed: 1322.75% (49 seconds)
./mame64 -bench 50 starwars -> Average speed: 548.97% (49 seconds)
./mame64 -bench 50 jedi -> Average speed: 375.08% (49 seconds)
After:
./mame64 -bench 50 missile -> Average speed: 1503.10% (49 seconds)
./mame64 -bench 50 starwars -> Average speed: 648.10% (49 seconds)
./mame64 -bench 50 jedi -> Average speed: 444.25% (49 seconds)

Signed-off-by: Andreas Müller <schnitzeltony@gmail.com>

* pokey: remove unused macros

Signed-off-by: Andreas Müller <schnitzeltony@gmail.com>
This commit is contained in:
Andreas Müller 2019-03-09 05:43:57 +00:00 committed by ajrhacker
parent dc6c49f98f
commit 107fff092e
2 changed files with 33 additions and 17 deletions
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46
src/devices/sound/pokey.cpp
View File

@ -99,11 +99,6 @@
#define TIMER2 1
#define TIMER4 2
/* values to add to the divisors for the different modes */
#define DIVADD_LOCLK 1
#define DIVADD_HICLK 4
#define DIVADD_HICLK_JOINED 7
/* AUDCx */
#define NOTPOLY5 0x80 /* selects POLY5 or direct CLOCK */
#define POLY4 0x40 /* selects POLY4 or POLY17 */
@ -152,11 +147,6 @@
#define DIV_64 28 /* divisor for 1.78979 MHz clock to 63.9211 kHz */
#define DIV_15 114 /* divisor for 1.78979 MHz clock to 15.6999 kHz */
#define P4(chip) chip->poly4[chip->p4]
#define P5(chip) chip->poly5[chip->p5]
#define P9(chip) chip->poly9[chip->p9]
#define P17(chip) chip->poly17[chip->p17]
#define CLK_1 0
#define CLK_28 1
#define CLK_114 2
@ -253,6 +243,7 @@ void pokey_device::device_start()
m_out_filter = 0;
m_out_raw = 0;
m_old_raw_inval = true;
m_borrow_all_max = 0;
m_kbd_state = 0;
/* reset more internal state */
@ -591,15 +582,34 @@ void pokey_device::step_one_clock(void)
clock_triggered[CLK_114] = 1;
}
/* in case
* no channel is at high speed AND
* no prescaler-clock has triggered AND
* we are not expecting a borrow-count finish
* => we are done and can exit here
*
* Note: for best performance on no-match case (matching case has to ask
* for all conditions anyway), the sequence chosen is:
* most likely no-match -> least likely no-match */
if (!clock_triggered[CLK_28] && !clock_triggered[CLK_114] &&
m_borrow_all_max == 0 &&
(m_AUDCTL & (CH1_HICLK || CH3_HICLK)) == 0)
{
/* not quite: high speed potentiometer requires handling on each
* cycle */
if ((m_SKCTL & SK_PADDLE) && (m_pot_counter < 228))
step_pot();
return;
}
int const base_clock = (m_AUDCTL & CLK_15KHZ) ? CLK_114 : CLK_28;
int clk = (m_AUDCTL & CH1_HICLK) ? CLK_1 : base_clock;
if (clock_triggered[clk])
/* increment CHAN1 & CHAN3 at each cycle for high speed or on prescaler
* clock trigger */
if ((m_AUDCTL & CH1_HICLK) || clock_triggered[base_clock])
m_channel[CHAN1].inc_chan();
clk = (m_AUDCTL & CH3_HICLK) ? CLK_1 : base_clock;
if (clock_triggered[clk])
if ((m_AUDCTL & CH3_HICLK) || clock_triggered[base_clock])
m_channel[CHAN3].inc_chan();
/* same for CHAN2 & CHAN4 - if not joined as upper bits */
if (clock_triggered[base_clock])
{
if (!(m_AUDCTL & CH12_JOINED))
@ -617,6 +627,10 @@ void pokey_device::step_one_clock(void)
step_keyboard();
}
/* performance-cheap decrement of shared helper max borrow counter */
if(m_borrow_all_max != 0)
m_borrow_all_max--;
/* do CHAN2 before CHAN1 because CHAN1 may set borrow! */
if (m_channel[CHAN2].check_borrow())
{

4
src/devices/sound/pokey.h
View File

@ -242,7 +242,8 @@ private:
m_counter = (m_counter + 1) & 0xff;
if (m_counter == 0 && m_borrow_cnt == 0)
{
m_borrow_cnt = 3;
m_borrow_cnt = m_parent->m_borrow_all_max = 3;
if (m_parent->m_IRQEN & m_INTMask)
{
/* Exposed state has changed: This should only be updated after a resync ... */
@ -286,6 +287,7 @@ private:
uint32_t m_out_raw; /* raw output */
bool m_old_raw_inval; /* true: recalc m_out_raw required */
uint32_t m_borrow_all_max; /* max borrow count for all channels */
double m_out_filter; /* filtered output */
int32_t m_clock_cnt[3]; /* clock counters */